Tectonic and morphosedimentary features of the 2010 Chile earthquake and tsunami in the Arauco Gulf and Mataquito River (Central Chile)

•Land deformation, run up, inundation extent and deposit extent and thickness were measured in the field after the earthquake.•Coseismic deformation measured by means of bio- and geomorphic markers agrees both with model deformation and measured GPS.•No relationship was found between coseismic land deformations, tsunami run-up and sedimentological features.

Effects of the 2010 Chilean earthquake and tsunami were evaluated at coastal sites between two zones of different coseismic deformations. Land deformation, run-up, inundation extent and deposit extent and thickness were measured in the field, providing insights into the processes and morphological changes associated with tsunami inundation and backwash. Three to five waves, of up to 10 m height, deposited several related layers along the coast, the thickness of these sandy deposits does not exceed 80 cm, and is generally less than 30 cm. Coseismic deformation measured by means of bio- and geomorphic markers agrees well both with model deformation and measured GPS. There is no relationship between the run-up height and the trend of coseismic deformation (uplift or subsidence), mainly because the effects of the tsunami were influenced locally by offshore bathymetry and coastal morphology.